Cable television system and method for providing cable television service using the system

ABSTRACT

Herein are disclosed a cable television system, mobile communication terminal, a relay apparatus, a center apparatus, and a method of providing a cable television service using the system, which enable a user operating a CATV mobile terminal ( 6 ) to receive a CATV service regardless of the service area of the CATV station where the user is located. When a vehicle ( 5 ) having a CATV mobile terminal ( 6 ) mounted thereon moves into a service area of a CATV station ( 3, 4 ), the CATV mobile terminal ( 6 ) is operated to transmit a log-in request to the CATV station ( 3, 4 ). The CATV station ( 3, 4 ) is operated to inquire about the user to the subscriber station ( 2 ), and the subscriber station ( 2 ) is operated to judge whether or not the user is authentic. Subscriber station ( 2 ) is operated to deliver common contents to the CATV mobile terminal ( 6 ) through the CATV station ( 3, 4 ) when it is judged that the user is authentic.

TECHNICAL FIELD OF INVENTION

The present invention relates to a cable television system, a relayapparatus, a center apparatus, and a method of providing a cabletelevision service, which enable a mobile communication terminal toreceive common contents delivered from a center apparatus through arelay apparatus installed in a service area even though the mobilecommunication terminal moves from one service area to another servicearea.

BACKGROUND ART

Up until now, there have been proposed a wide variety of systems forproviding a cable television service, hereinlater simply referred to as“CATV service”. The CATV service includes a television broadcastingservice provided from a plurality of cable television stations for afringe and local area, and a service for a connection with a computercommunication network such as for example an internet.

The broadcasting programs of this CATV service include contentsconcerning a weather forecast, traffic information, a program of anevent, music, a movie, and the like. A user subscribes to a cabletelevision station, hereinlater simply referred to as “CATV station” ina service area where he or she lives, to have a dedicated connectionline laid from the CATV station to his or her room. The user receivesthe contents through the dedicated line, and pays a fee charged inexchange for the contents to the CATV station.

The conventional CATV system, however, encounters a drawback that theuser cannot receive the contents from the CATV station using a mobilecommunication terminal such as, for example, CATV mobile mounted on avehicle resulting from the fact that the user receives the contentsthrough the dedicated line.

The conventional CATV system encounters another drawback that the usercannot receive any CATV service when the user moves into a service areaother than the service area of the CATV station to which the user hassubscribed resulting from the fact that the user subscribes to the CATVstation in the related service area.

It is, therefore, an object of the present invention to provide a systemwhich makes it possible for a user to receive contents from the CATVstation using a mobile communication terminal regardless of whether ornot the user moves into a service area other than the service area ofthe CATV station to which the user has subscribed.

The present invention is made with a view to overcoming the abovementioned drawbacks and is directed to a cable television system, arelay apparatus, a center apparatus, and a cable television providingmethod, which enable a mobile communication terminal to receive commoncontents delivered from a center apparatus through each of a pluralityof relay apparatuses respectively installed in a plurality of serviceareas even though the mobile communication terminal moves from oneservice area to another service area.

DISCLOSURE OF THE INVENTION

According to one aspect of the present invention, there is provided acable television system, comprising: a mobile communication terminalmounted on a movable object and capable of establishing a connectionwith a cable television service line by wireless; a plurality of relayapparatuses respectively installed in a plurality of service areas, andeach of the relay apparatuses being operative to deliver common contentsconcerning a cable television service to the mobile communicationterminal located within each of the service areas; and a centerapparatus connected with each of the relay apparatuses through acommunication line, for delivering common contents to the relayapparatuses by way of multicast communication, and in which the mobilecommunication terminal located within a service area is operative totransmit a log-in request to the relay apparatus installed in theservice area by wireless, the relay apparatus is operative to transmituser identification information of the mobile communication terminal andspecifying information for specifying the relay apparatus to the centerapparatus, the center apparatus is operative to transmit authenticationinformation to the relay apparatus, which have transmitted thespecifying information, when the user identification information isvalid, upon receiving the specifying information, the relay apparatus isoperative to start a cable television service for the mobilecommunication terminal on the basis of the authentication information,upon receiving the authentication information, the mobile communicationterminal is operative to transmit request information for commoncontents to the relay apparatus, the relay apparatus is operative totransmit a request for delivering common contents to the centerapparatus, upon receiving the request information for common contentsfrom the mobile communication terminal, and the center apparatus isoperative to deliver common contents to the mobile communicationterminal through the relay apparatus and store therein and managedelivery history information indicative of a history of deliveringcontents, in response to the request for delivering common contents fromthe relay apparatus.

In accordance with the above construction, in the cable televisionsystem according to the present invention, the mobile communicationterminal is operative to transmit a log-in request to the relayapparatus in the event that the movable object having the mobilecommunication terminal mounted thereon moves into the service area ofthe relay apparatus, the relay apparatus is operative to transmit anauthentication request to the center apparatus, and the center apparatusis operative to deliver common contents (music, a movie, news, a weatherforecast, a variety program, and the like) to the mobile communicationterminal when the user is judged to be authentic. The cable televisionsystem thus constructed makes it possible for the mobile communicationterminal to receive common contents from the center apparatus eventhough the mobile communication terminal moves from one service area toanother service area of any one of the relay apparatuses.

In addition, a plurality of relay apparatuses are connected with thecenter apparatus through a communication line. The fact that each of therelay apparatuses can deliver common contents to the mobilecommunication terminal through the communication line leads to the factsthat the need of dedicated lines connecting the center apparatus withthe relay apparatuses is eliminated, and each of the relay apparatusescan easily communicate with the mobile communication terminal throughthe center apparatus.

Further, the center apparatus is operative to judge whether or not theuser identification information is authentic, and deliver the commoncontents stored therein to the mobile communication terminal through therelay apparatuses, thereby enabling the center apparatus to manage allof the delivery history information in association with useridentification information.

Still further, the center apparatus can deliver the contents by way ofmulticast communication. This leads to the fact that the centerapparatus and the relay apparatuses can utilize IP services such as forexample an internet, thereby effectively utilizing the network resourcepotentially present in the communication line.

In the cable television system according to the present invention, theuser identification information may be constituted by personalinformation stored in an IC (integrated circuit) card or a magneticcard.

In accordance with the above construction, the center apparatus caneasily identify the user even though the user operates a plurality ofmobile communication terminals as well as authenticate the validity ofthe user on the basis of the personal information (e.g., ID), therebyprotecting the common contents from unauthorized use.

In the cable television system according to the present invention, thecenter apparatus may be operative to perform an accounting process onthe basis of the delivery history information indicative of deliveringthe common contents.

In accordance with the above construction, the center apparatus canmanage all of the delivery history information and the relay apparatusesare not required to perform the accounting process, thereby improvingthe efficiency of the accounting process.

According to another aspect of the present invention, there is provideda relay apparatus, installed in a service area and connected with acenter apparatus through a communication line, for delivering commoncontents concerning a cable television service received from the centerapparatus to a mobile communication terminal mounted on a movable objectlocated within the service area, the relay apparatus comprises: firstreceiving means for receiving the log-in request when the mobilecommunication terminal transmit a log-in request from the mobilecommunication terminal by wireless; transmitting means for transmittinguser identification information of the mobile communication terminal andspecifying information for specifying the relay apparatus, which hasreceived the log-in request and the user identification information, tothe center apparatus upon receiving the log-in request; second receivingmeans for receiving authentication information from the center apparatuswhen the user identification information is valid; service providingmeans for starting a cable television service for the mobilecommunication terminal on the basis of the authentication information;common content request means for transmitting a request for deliveringcommon contents to the center apparatus, upon receiving requestinformation for common contents from the mobile communication terminal;and delivering means for delivering common contents received from thecenter apparatus to the mobile communication terminal.

In accordance with the above construction, in the cable televisionsystem according to the present invention, the mobile communicationterminal is operative to transmit a log-in request to the relayapparatus in the event that the movable object having the mobilecommunication terminal mounted thereon moves into the service area ofthe relay apparatus, the relay apparatus is operative to transmit anauthentication request to the center apparatus, and the center apparatusis operative to deliver common contents (music, a movie, news, a weatherforecast, a variety program, and the like) to the mobile communicationterminal when the user is judged to be authentic. The cable televisionsystem thus constructed makes it possible for the mobile communicationterminal to receive common contents from the center apparatus eventhough the mobile communication terminal moves from one service area toanother service area of any one of the relay apparatuses.

In addition, a plurality of relay apparatuses are connected with thecenter apparatus through a communication line. The fact that each of therelay apparatuses can deliver common contents to the mobilecommunication terminal through the communication line leads to the factsthat the need of dedicated lines connecting the center apparatus withthe relay apparatuses is eliminated, and each of the relay apparatusescan easily communicate with the mobile communication terminal throughthe center apparatus.

In the relay apparatus according to the present invention, the useridentification information may be constituted by personal informationstored in an IC (integrated circuit) card or a magnetic card.

In accordance with the above construction, the center apparatus caneasily identify the user even though the user operates a plurality ofmobile communication terminals as well as authenticate the validity ofthe user on the basis of the personal information (e.g., ID), therebyprotecting the common contents from unauthorized use.

According to a further aspect of the present invention, there isprovided a center apparatus for delivering common contents to aplurality of relay apparatuses respectively installed in a plurality ofservice areas by way of multicast communication so that each of therelay apparatuses delivers common contents concerning a cable televisionservice to a mobile communication terminal located within each of theservice areas, the center apparatus comprising: first receiving meansfor receiving user identification information and specifying informationfor specifying the relay apparatus; specific information storage meansfor storing therein personal information on user; transmitting means forjudging whether or not the user identification information is authenticby comparing the personal information stored in the specific informationstorage means with the user identification information and transmittingauthentic information to the relay apparatus specified by the specifyinginformation when it is judged that the user identification informationis authentic; second receiving means for receiving a request fordelivering common contents from the relay apparatus; and deliveringmeans for delivering common contents to the mobile communicationterminal through the relay apparatus upon receiving the request fordelivering common contents from the relay apparatus.

In accordance with the above construction, in the cable televisionsystem according to the present invention, the mobile communicationterminal is operative to transmit a log-in request to the relayapparatus in the event that the movable object having the mobilecommunication terminal mounted thereon moves into the service area ofthe relay apparatus, the relay apparatus is operative to transmit anauthentication request to the center apparatus, and the center apparatusis operative to deliver common contents (music, a movie, news, a weatherforecast, a variety program, and the like) to the mobile communicationterminal when the user is judged to be authentic. The cable televisionsystem thus constructed makes it possible for the mobile communicationterminal to receive common contents from the center apparatus eventhough the mobile communication terminal moves from one service area toanother service area of any one of the relay apparatuses.

In addition, a plurality of relay apparatuses are connected with thecenter apparatus through a communication line. The fact that each of therelay apparatuses can deliver common contents to the mobilecommunication terminal through the communication line leads to the factsthat the need of dedicated lines connecting the center apparatus withthe relay apparatuses is eliminated, and each of the relay apparatusescan easily communicate with the mobile communication terminal throughthe center apparatus.

Further, the center apparatus is operative to judge whether or not theuser identification information is authentic, and deliver the commoncontents stored therein to the mobile communication terminal through therelay apparatuses, thereby enabling the center apparatus to manage allof the delivery history information in association with useridentification information.

Still further, the center apparatus can deliver the contents by way ofmulticast communication. This leads to the fact that the centerapparatus and the relay apparatuses can utilize IP services such as forexample an internet, thereby effectively utilizing the network resourcepotentially present in the communication line.

The center apparatus according to the present invention may furthercomprise storage means for storing therein delivery history informationindicative of a history of delivering the contents; and accounting meansfor performing an accounting process on the basis of the deliveryhistory information stored in the storage means.

In accordance with the above construction, the center apparatus canmanage all of the delivery history information and the relay apparatusesare not required to perform the accounting process, thereby improvingthe efficiency of the accounting process.

In the center apparatus according to the present invention, the useridentification information may be constituted by personal informationstored in an IC (integrated circuit) card or a magnetic card.

In accordance with the above construction, the center apparatus caneasily identify the user even though the user operates a plurality ofmobile communication terminals as well as authenticate the validity ofthe user on the basis of the personal information (e.g., ID), therebyprotecting the common contents from unauthorized use.

According to a still further aspect of the present invention, there isprovided a method of providing a cable television service of providing acable television service to a mobile communication terminal through arelay apparatus from a center apparatus, comprising; (a) preparing amobile communication terminal mounted on a movable object and capable ofestablishing a connection with a cable television service line bywireless; a plurality of relay apparatuses respectively installed in aplurality of service areas, and each of the relay apparatuses beingoperative to deliver common contents concerning a cable televisionservice to the mobile communication terminal located within each of theservice areas; and a center apparatus connected with each of the relayapparatuses through a communication line, for delivering common contentsto the relay apparatuses by way of multicast communication; (b)transmitting a log-in request to the relay apparatus installed in theservice area by wireless, by the mobile communication terminal; (c)transmitting user identification information of the mobile communicationterminal and specifying information for specifying the relay apparatusto the center apparatus, by the relay apparatus; (d) transmittingauthentication information to the relay apparatus, which havetransmitted the specifying information, when the user identificationinformation is valid, upon receiving the specifying information, by thecenter apparatus; (e) starting a cable television service for the mobilecommunication terminal on the basis of the authentication information,by the relay apparatus; (f) transmitting request information for commoncontents to the relay apparatus, by the mobile communication terminal;(g) transmitting a request for delivering common contents to the centerapparatus, upon receiving the request information for common contentsfrom the mobile communication terminal, by the relay apparatus; (h)delivering common contents to the mobile communication terminal throughthe relay apparatus in response to the request for delivering commoncontents from the relay apparatus, by the center apparatus; and (i)storing therein and managing delivery history information indicative ofa history of delivering contents.

In accordance with the above method, the mobile communication terminalis operative to transmit a log-in request to the relay apparatus in theevent that the movable object having the mobile communication terminalmounted thereon moves into the service area of the relay apparatus, therelay apparatus is operative to transmit an authentication request tothe center apparatus, and the center apparatus is operative to delivercommon contents (music, a movie, news, a weather forecast, a varietyprogram, and the like) to the mobile communication terminal when theuser is judged to be authentic. The cable television system thusconstructed makes it possible for the mobile communication terminal toreceive common contents from the center apparatus even though the mobilecommunication terminal moves from one service area to another servicearea of any one of the relay apparatuses.

In addition, a plurality of relay apparatuses are connected with thecenter apparatus through a communication line. The fact that each of therelay apparatuses can deliver common contents to the mobilecommunication terminal through the communication line leads to the factsthat the need of dedicated lines connecting the center apparatus withthe relay apparatuses is eliminated, and each of the relay apparatusescan easily communicate with the mobile communication terminal throughthe center apparatus.

Further, the center apparatus is operative to judge whether or not theuser identification information is authentic, and deliver the commoncontents stored therein to the mobile communication terminal through therelay apparatuses, thereby enabling the center apparatus to manage allof the delivery history information in association with useridentification information.

Still further, the center apparatus can deliver the contents by way ofmulticast communication. This leads to the fact that the centerapparatus and the relay apparatuses can utilize IP services such as forexample an internet, thereby effectively utilizing the network resourcepotentially present in the communication line.

In the method of providing a cable television service according to thepresent invention, the user identification information may beconstituted by personal information stored in an IC (integrated circuit)card or a magnetic card.

In accordance with the above construction, the center apparatus caneasily identify the user even though the user operates a plurality ofmobile communication terminals as well as authenticate the validity ofthe user on the basis of the personal information (e.g., ID), therebyprotecting the common contents from unauthorized use.

In the method of providing a cable television service, the step (i) mayhave a step of performing an accounting process on the basis of thedelivery history information indicative of delivering the commoncontents. In accordance with the above construction, the centerapparatus can manage all of the delivery history information and therelay apparatuses are not required to perform the accounting process,thereby improving the efficiency of the accounting process.

Further the more, the relay apparatuses may have respective own originalcontents, and transmit the original contents to one another, and theCATV mobile terminal may obtain contents delivered not only from thesubscriber station but also from the CATV stations, to which the userhas not subscribed.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and advantage of a cable television system and a method ofproviding a cable television service using the system according to thepresent invention will become apparent as the description proceeds whentaken in conjunction with the accompanying drawings.

FIG. 1 is a schematic diagram showing preferred embodiments of a cabletelevision system, a relay apparatus, a center apparatus, and a cabletelevision service providing method according to the present invention.

FIG. 2 is a block diagram showing routes through which the contents aredelivered in the preferred embodiments of the cable television system,the relay apparatus, the center apparatus, and the cable televisionservice providing method according to the present invention.

FIG. 3 is a block diagram showing the relay apparatus, the centerapparatus, and the mobile communication terminal forming part of thepreferred embodiments of the cable television system, the relayapparatus, the center apparatus, and the cable television serviceproviding method according to the present invention.

FIG. 4 is a diagram showing flows of delivering common contents in thepreferred embodiments of the cable television system, the relayapparatus, the center apparatus, and the cable television serviceproviding method according to the present invention.

FIG. 5 is a diagram showing flows of user authentication and accountingprocesses performed in the preferred embodiments of the cable televisionsystem, the relay apparatus, the center apparatus, and the cabletelevision service providing method according to the present invention.

FIG. 6 is a schematic diagram showing preferred embodiments of a cabletelevision system, a relay apparatus, a center apparatus, and a cabletelevision service providing method according to the present invention.

FIG. 7 is a diagram showing flows of delivering common contents in thepreferred embodiments of the cable television system, the relayapparatus, the center apparatus, and the cable television serviceproviding method according to the present invention.

BEST MODE OF CARRYING OUT THE PRESENT INVENTION

The preferred embodiment of the present invention will be describedhereinafter with reference to the drawings.

FIGS. 1 through 5 are diagrams showing preferred embodiments of a cabletelevision system, a relay apparatus, a center apparatus, and a cabletelevision service providing method according to the present invention.

The construction will be described first. The cable television system isshown in FIGS. 1 and 2 to bear a reference numeral 1 and comprises asubscriber station (center apparatus) 2, CATV stations, i.e., a CATV-A,a CATV-B, a CATV-C, and a CATV-D for delivering contents concerning acable television service under the control of the subscriber station 2,a CATV mobile terminal (mobile communication terminal) 6 mounted on avehicle (movable object) 5 and receiving the contents from the CATV-A(hereinlater referred to as “CATV station 3”), a CATV-B (hereinlaterreferred to as “CATV station 4”), a CATV-C, and a CATV-D. The subscriberstation 2 is connected with the CATV stations 3 and 4 through acommunication line 7 such as for example a leased line, a dedicatedline, a wide-area LAN, or the like. The communication line 7 permits thesubscriber station 2, the CATV stations 3, 4, and other stations tocommunicate with one another at high speed by way of multicastcommunication.

While there are shown four CATV stations in FIG. 1, the cable televisionsystem 1 may, in reality, comprise more than four CATV stations. In FIG.2, there are shown only two CATV stations, namely, the CATV stations 3and 4, for the purpose of simplifying the description and assisting inunderstanding about the whole operation.

As best shown in FIG. 2, the CATV stations 3 and 4 respectively comprisea plurality of radio transmitting and receiving devices 3 a and 4 ainstalled in respective service areas as communication lines, therebymaking it possible for the CATV stations 3 and 4 to deliver the contents(music, a movie, news, a weather forecast, a variety program, and thelike) to the CATV mobile terminal 6 located within their respectiveservice areas.

The CATV mobile terminal 6 is shown in FIG. 3 comprising a mobilestation transmitting and receiving device 10, a digital set top box(D-STB) 11, an IC card reader (reading and writing means) 12, a cablemodem 13, a CPU (personal computer) 14, a display 15, and a memory 16.

The mobile station transmitting and receiving device 10 is designed totransmit and receive a signal with each of the radio transmitting andreceiving devices 3 a and 4 a when entered into the service area of eachof the CATV stations 3 and 4 to ensure that the CATV mobile terminal 6communicates with each of the CATV stations 3 and 4 by wireless. TheD-STB 11 is designed to process the signals received and transmittedwith each of the radio transmitting and receiving devices 3 a and 4 a toperform bidirectional communications.

The IC card reader 12 is designed to have an IC card inserted thereinto,and read out, as user identification information, ID, personalinformation (e.g., a bank account, an address), and the like from the ICcard. The user identification information is transmitted by the D-STB 11to the radio transmitting and receiving device 3 a and/or 4 a throughthe mobile station transmitting and receiving device 10.

The cable modem 13 is adapted to demodulate the contents data containedin the signal received by the mobile station transmitting and receivingdevice 10. The contents thus demodulated are reproduced by the display15.

The CPU 14 is adapted to control the whole operation of the CATV mobileterminal 6. The CPU 14 is operative to control, for example, the IC cardreader 12 to have the IC card reader 12 read out from the IC card theuser identification information to be outputted therethrough. Further,the CPU 14 is operative to control the mobile station transmitting andreceiving device 10 to have the mobile station transmitting andreceiving device 10 transmits a log-in request when the vehicle 5 movesinto a service area of the CATV station 3 or 4.

The memory 16 is adapted to store therein utilization historyinformation indicative of a history of utilizing the contents receivedfrom the CATV station 3 or CATV station 4 in response to instructionsfrom the CPU 14.

The CATV stations 3 and 4 respectively comprises radio frequency (RF)multiplexing devices 21 and 31, CATV image transmitting devices 45 and46, Web servers 25 and 35, animation servers 26 and 36, operationterminals 27 and 37, subscriber authentication servers 28 and 38, cablemodem centers 29 and 39, and routers 30 and 40.

The radio frequency (RF) multiplexing devices 21 and 31 are adapted toestablish radio communications with the CATV mobile terminal 6respectively through the radio transmitting and receiving devices 3 aand 4 a.

The CATV image transmitting devices 45 and 46 are adapted to delivercontents of digital image in the format such as for example MPEG formatthrough CATV lines. The CATV image transmitting devices 45 and 46 arerespectively constituted by CS tuners 24 and 34 for receiving imagedata, MPEG encoders 23 and 33 for compressing the image data, and 64 QAMmodulators (QAM MOD) 22 and 32 for modulating the image data compressedby the MPEG encoders 23 and 33 into data signals of a predeterminedformat to be delivered through the CATV lines. The data signals thusdelivered are later converted into images by the D-STB of the CATVmobile terminal. In the present embodiment, the CS tuners 24 and 34 maytransfer to the MPEG encoders 23 and 33 the image data stored in a videotape, optical disc, or the like.

The Web servers 25 and 35 are connectable with an internet, and adaptedto deliver and obtain various contents through the internet. Theanimation servers 26 and 36 are adapted to input the contents ofanimation data such as for example a movie, music, a weather forecast,and news from the subscriber station 2, and deliver the contents thusinputted to the CATV mobile terminal 6. The operation terminals 27 and37 are adapted to permit a user to operate various functions of the CATVstations 3 and 4.

The subscriber authentication servers 28 and 38 are adapted to storetherein user's personal information (e.g., ID and accountinginformation). When the CATV mobile terminal 6 is located in the servicearea of each of the CATV stations 3 and 4 and transmits a log-inrequest, each of the subscriber authentication servers 28 and 38 isoperative to select the user's personal information corresponding to theCATV mobile terminal 6 from among the user's personal information storedtherein, and request the subscriber station 2 to start an authenticationprocess on the user identification information.

Each of the routers 30 and 40 is connected with the wide-area LAN 7 andadapted to carry out predetermined protocols and communicate with thesubscriber station 2 and other CATV stations through the wide-area LAN7.

In the present embodiment, the subscriber authentication servers 28 and38 are operative to receive the log-in request through the routers 30and 40 when the CATV mobile terminal 6 transmits a log-in request to theCATV stations 3 and 4 by wireless. The subscriber authentication serverand the router constitute first receiving means.

Further, in the present embodiment, the subscriber authentication server28 or 38 is operative to transmit user identification information andspecifying information (IP address) for specifying the CATV station 3 or4, which has received the log-in request, to the subscriber station 2through the router 30 or 40 upon receiving the log-in request from theCATV mobile terminal 6 through the radio transmitting and receivingdevice 3 a or 4 a. The subscriber authentication server and the routerconstitute transmitting means.

The subscriber authentication servers 28 and 38 are adapted to receiveauthentication information from the subscriber station 2 through therouters 30 and 40 when the user identification information is judged tobe valid by the subscriber station 2, which will be described later. Thesubscriber authentication server and the router constitute secondreceiving means.

Further, the animation servers 26 and 36 are operative to start a cabletelevision service for the CATV mobile terminal 6 on the basis of theauthentication information received by the subscriber authenticationservers 28 and 38. The animation server constitutes service providingmeans. The service provided by the CATV station 3 or 4 for the CATVmobile terminal 6 includes a list of contents such as for example musicand news to be delivered from the subscriber station 2 to the CATVmobile terminal 6, and an IP address, a port number, and the likerequired to establish a connection with the subscriber station 2.

In the CATV mobile terminal 6, the display 15 is operative to displaythe list of contents upon receiving a list of contents from the CATVstation 3 or 4, the CPU 14 is operative to allow the user to selectdesired contents from the list, and transmit content request informationindicative of the desired contents to the CATV station 3 or 4.

In the CATV station 3 or 4, upon receiving the content requestinformation indicative of the desired contents from the CATV mobileterminal 6, the subscriber authentication server 28 or 38 is operativeto transmit an IGMP (Internet Group management Protocol) connectionrequest to the subscriber station 2 through the router 30 or 40 on thebasis of the content request information under the condition that thecontent request information includes the IP address and the port numberrequired to obtain the desired contents. In the present embodiment, thesubscriber authentication server and the router constitute commoncontent request means.

The animation servers 26 and 36 are operative to start delivering thedesired contents to the CATV mobile terminal 6 by wireless through theradio frequency (RF) multiplexing devices 21 and 31 and the radiotransmitting and receiving devices 3 a and 4 a immediately in responseto the content request information from the CATV mobile terminal 6.

The subscriber station 2 comprises a router 41, an authentication server42, a multicast server 43, and a content managing unit 44, and anencoder 47.

The router 41 is connected with a wide-area LAN 7 and adapted to carryout predetermined protocols and communicate with the CATV stations 3 and4 through the wide-area LAN 7.

The authentication server 42 includes a user-specific informationstorage unit (database) 42 a having stored therein user's personalinformation (ID, a CATV station which the user has subscribed to, anaccounting record, a bank account, an address, and the like) anddelivery history information indicative of a history of delivering thecontents (see FIG. 1). The user-specific information storage unit 42 aconstitutes specific information storage means.

The authentication server 42 is adapted to receive user identificationinformation and an IP address specifying the CATV station 3 or 4 fromthe CATV station 3 or 4 through the router 41. The authentication server42 and the router 41 constitute first receiving means. Theauthentication server 42 is operative to judge whether or not the useridentification information is authentic by comparing the personalinformation stored in the user-specific information storage unit 42 awith the user identification information received from the CATV station3 or 4, and transmit authentic information to the CATV station 3 or 4specified by the IP address when it is judged that the useridentification information is authentic. The authentication server 42and the router 41 constitute transmitting means.

The multicast server 43 is adapted to receive a request for deliveringcommon contents from the CATV station 3 or 4 through the router 41. Inthe present embodiment, the multicast server 43 and the router 41constitute second receiving means. Upon receiving the request fordelivering common contents, the encoder 47 is operative to compress thecommon contents (music, a movie, news, a weather forecast, a varietyprogram, and the like) managed by the content managing unit 44, and themulticast server 43 is operative to transmit the common contents thuscompressed to the CATV mobile terminal 6 through the CATV station 3 or 4by way of multicast communication. The multicast server 43 and therouter 41 constitute delivering means.

Furthermore, the authentication server 42 is operative to store thereindelivery history information indicative of a history of delivering thecontents delivered by the multicast server 43 in association with user'sIDs and IP addresses of the CATV stations 3 and 4, and perform anaccounting process on the basis of the delivery history information thusstored. In the present embodiment, the authentication server 42constitutes accounting means.

While it has been described in the present embodiment appearing in FIG.2 that the subscriber station 2 comprises an authentication server 42and a multicast server 43, however, the cable television system 1according to the present invention is not limited to the presentembodiment. Either one of the authentication server 42 and the multicastserver 43 may be mounted on the CATV station 3 or the CATV station 4, orinstalled separately from the subscriber station 2 and the CATV stations3 and 4.

The method of providing a cable television service will be describedhereinlater with reference to FIGS. 4 and 5. FIG. 4 is a flowchartshowing a flow of delivering common contents. FIG. 5 is a flow chartshowing flows of user authentication and accounting processes performedwhile the common contents are delivered.

As shown in FIGS. 4 and 5, the multicast server 43 of the subscriberstation 2 is operated to deliver contents guidance informationindicative of available contents to the CATV stations 3 and 4. Thesubscriber station 2 has not yet established an IGMP connection (IGMPJOIN) with the CATV stations 3 and 4. Accordingly, the multicastcontents can not be delivered to the CATV stations 3 and 4.

When the vehicle 5 having the CATV mobile terminal 6 mounted thereonmoves into the CATV station 3 (hereinlater referred to as “CATV-A”), theCATV mobile terminal 6 is operated to transmit a log-in request to theCATV-A.

The CATV-A is operated to transmit a signal notifying the log-in requestto the subscriber station 2. The subscriber station 2 is operated totransmit a signal requesting for user identification information (userID) of the CATV mobile terminal 6 to the CATV-A. The CATV-A is operatedto transmit a signal requesting for the user identification informationto the CATV mobile terminal 6.

The CATV mobile terminal 6 is operated to transmit an authenticationrequest signal with the user identification information (ID) read out bythe ID card reader 12 to the CATV-A. The CATV-A is operated to transmitthe authentication request signal with the user identificationinformation to the subscriber station 2.

The subscriber station 2 is operated to judge whether or not the useridentification information is authentic by comparing the personalinformation stored in the user-specific information storage unit 42 awith the user identification information received from the CATV-A, andtransmit authentic information to the CATV-A when it is judged that theuser identification information is authentic. More specifically, thesubscriber station is operated to judge whether or not the user hassubscribed to any one of the CATV stations connected with the subscriberstation 2 and never failed to pay fee for the CATV service whilecomparing the personal information stored in the user-specificinformation storage unit 42 a with the user identification informationreceived from the CATV-A. The user is judged to be authentic under thecondition that the user has subscribed to any one of the CATV stationsconnected with the subscriber station 2 and never failed to pay fee forthe CATV service.

The CATV-A is operated to start a cable television service for the CATVmobile terminal 6. The CATV-A is operated to transmit to the CATV mobileterminal 6 authentication information (e.g., local IP address) requiredto establish a connection with the subscriber station 2, and a list ofcontents available for the CATV mobile terminal 6.

The CATV mobile terminal 6 is operated to select desired contents fromthe list, and transmit content request information indicative of thedesired contents to the CATV-A.

Upon receiving the content request information from the CATV mobileterminal 6, the CATV-A is operated to transmit an IP address and a portnumber corresponding to the content request information, and an IGMP(Internet Group management Protocol) connection request to thesubscriber station 2.

The subscriber station 2 is operated to establish an IGMP connectionwith the CATV-A: The multicast server 43 of the subscriber station 2 isoperated to deliver the multicast contents to the CATV mobile terminal 6through the CATV-A, and store delivery history information indicative ofa history of delivering the contents in the user-specific informationstorage unit 42 a.

Upon receiving a request for the accounting service from the CATV mobileterminal 6, the CATV-A is operated to transfer the request for theaccounting service to the subscriber station 2. In the subscriberstation 2, the authentication server 42 is operated to perform anaccounting process on the basis of the delivery history informationstored in the user-specific information storage unit 42 a. Thesubscriber station 2 is operated to transmit the result of theaccounting process to the CATV-A, and the CATV-A is then operated totransmit the accounting information to the CATV mobile terminal 6.

When, on the other hand, the vehicle 5 having the CATV mobile terminal 6mounted thereon moves into the CATV station 4 (hereinlater referred toas “CATV-B”), the CATV mobile terminal 6 is operated to transmit alog-in request to the CATV-B.

The CATV-B is operated to transmit a signal notifying the log-in requestto the subscriber station 2. The subscriber station 2 is operated totransmit a signal requesting for user identification information (userID) of the CATV mobile terminal 6 to the CATV-B. The CATV-B is operatedto transmit a signal requesting for the user identification informationto the CATV mobile terminal 6.

The CATV mobile terminal 6 is operated to transmit an authenticationrequest signal with the user identification information (ID) read out bythe ID card reader 12 to the CATV-B. The CATV-B is operated to transmitthe authentication request signal with the user identificationinformation to the subscriber station 2.

The subscriber station 2 is operated to judge whether or not the useridentification information is authentic by comparing the personalinformation stored in the user-specific information storage unit 42 awith the user identification information received from the CATV-B, andtransmit authentic information to the CATV-B when it is judged that theuser identification information is authentic.

The CATV-B is operated to start a cable television service for the CATVmobile terminal 6. The CATV-B is operated to transmit to the CATV mobileterminal 6 authentication information (e.g., local IP address) requiredto establish a connection with the subscriber station 2, and a list ofcontents available for the CATV mobile terminal 6.

The CATV mobile terminal 6 is operated to select desired contents fromthe list, and transmit content request information indicative of thedesired contents to the CATV-B.

Upon receiving the content request information from the CATV mobileterminal 6, the CATV-B is operated to transmit an IP address and a portnumber corresponding to the content request information, and an IGMP(Internet Group management Protocol) connection request to thesubscriber station 2.

The subscriber station 2 is operated to establish an IGMP connectionwith the CATV-B. The multicast server 43 of the subscriber station 2 isoperated to deliver the multicast contents to the CATV mobile terminal 6through the CATV-B and store delivery history information indicative ofa history of delivering the contents in the user-specific informationstorage unit 42 a.

Upon receiving a request for the accounting service from the CATV mobileterminal 6, the CATV-B is operated to transfer the request for theaccounting service to the subscriber station 2. In the subscriberstation 2, the authentication server 42 is operated to perform anaccounting process on the basis of the delivery history informationstored in the user-specific information storage unit 42 a. Thesubscriber station 2 is operated to transmit the result of theaccounting process to the CATV-B, and the CATV-B is then operated totransmit the accounting information to the CATV mobile terminal 6.

When the vehicle 5 having the CATV mobile terminal 6 mounted thereon,then, moves into the CATV-C, the CATV-D, . . . , or the CATV-n, the sameprocesses will be repeated.

As will be seen from the foregoing description, it is to be understoodthat the CATV mobile terminal 6 is operative to transmit a log-inrequest to the CATV station 3 or 4 in the event that the vehicle 5having the CATV mobile terminal 6 mounted thereon moves into the servicearea of the CATV station 3 or 4, the CATV-station 3 or 4 is operative totransmit an authentication request with the user identificationinformation of the CATV mobile terminal 6 to the subscriber station 2,and the subscriber station 2 is operative to deliver common contents tothe CATV mobile terminal 6 when the user is judged to be authentic. Thecable television system 1 thus constructed makes it possible for theCATV mobile terminal 6 to receive common contents from the subscriberstation 2 even though the CATV mobile terminal 6 moves from one servicearea to another service area of any one of the CATV stations 3 and 4.

Especially, when common contents are delivered to the CATV mobileterminal through a plurality of affiliated CATV stations, all of theaffiliated CATV stations are required to manage delivery historyinformation indicative of a history of delivering contents separatelyfrom one another, and operations, accordingly, tend to be overlappedamong the affiliated CATV stations. In the present embodiment, althoughthe common contents are delivered to the CATV mobile terminal 6 througha plurality of CATV stations 3 and 4, the subscriber station 2 isoperative to manage all of the delivery history information. This leadsto the fact that the CATV stations 3 and 4 are not required to managethe delivery history information, but simply serve as relay stations,thereby drastically reducing the operations overlapped among thesubscriber station 2, the CATV stations 3 and 4.

In addition, according to the present invention, a plurality of CATVstations 3 and 4 are connected with the subscriber station 2 through thewide-area LAN 7. The fact that each of the CATV stations 3 and 4 candeliver common contents to the CATV mobile terminal 6 through thewide-area LAN 7 leads to the facts that the need of laying dedicatedlines connecting the subscriber station 2 with CATV stations 3 and 4 iseliminated, and that the communication between each of the CATV stations3 and 4 and the CATV mobile terminal 6 through the subscriber station 2is greatly facilitated.

Further, according to the present invention, the subscriber station 2 isoperative to judge whether or not the user identification information(ID) is authentic, and deliver the common contents stored therein to theCATV mobile terminal 6 through the CATV stations 3 and 4, therebyenabling the subscriber station 2 to manage all of the delivery historyinformation in association with user identification information.

Still further, according to the present invention, the subscriberstation 2, the CATV stations 3, and 4 can communication with one anotherby way of multicast communication through the wide-area LAN 7. Thisleads to the fact that the subscriber station 2, the CATV stations 3,and 4 can utilize various IP services such as for example an internetaccess, thereby effectively utilizing the network resource potentiallypresent in the wide-area LAN 7.

In the present embodiment, as the user identification information isused personal information stored in an IC (integrated circuit) card. Thesubscriber station 2 thus constructed can identify the user even thoughthe user operates a plurality of CATV mobile terminals 6 as well asauthenticate the validity of the user on the basis of the personalinformation (e.g., ID), thereby protecting the common contents fromunauthorized use.

Especially, the conventional CATV system in which each of the CATVstations 3 and 4 is operative to authenticate the validity of the user,and separately manage delivery history information indicative of ahistory of delivered contents, each of the CATV stations is required toassign a local ID to the CATV mobile terminal 6 whenever the CATV mobileterminal 6 moves to the service area of each of the CATV stations,thereby complicating the management of the user information. In the casethat as the user identification information is used ID of the CATVmobile terminal 6, the CATV mobile terminal 6 cannot be protected fromunauthorized use in the event that the CATV mobile terminal 6 is stolen.

In the present embodiment as the user identification information is usedpersonal information stored in an IC (integrated circuit) card, and thesubscriber station 2 manages all of the delivery history information,thereby simplifying user management as well as protecting the CATVmobile terminal 6 from unauthorized use. The personal information may bestored in a magnetic card in place of the IC card.

In addition, in the present embodiment, the subscriber station 2 isoperative to perform an accounting process on the basis of the deliveryhistory information indicative of delivering the contents. The fact thatthe subscriber station 2 manages all of the delivery history informationleads to the fact that the CATV stations 3 and 4 are not required toperform the accounting process, thereby improving the efficiency ofoperations related to the accounting process.

Further, according to the present invention, each of the CATV stationsmay comprise a multicast server as shown in FIGS. 6 and 7. The cabletelevision system thus constructed makes it possible for the CATV mobileterminal moved into a service area of, for example, the CATV-A, to stillreceive the contents delivered from, for example, the CATV-C other thanthe CATV-A through the subscriber station 2.

Still further, according to the present invention, the subscriberstation may be replaced by an authentication station or content deliverystation, which performs all the operations related to content delivery,authentication, and accounting processes.

Further the more, while it has been described in the present embodimentthat the CATV mobile terminal obtains contents delivered from thesubscriber station and the CATV stations to which the user of the CATVmobile terminal has subscribed, according to the present invention, theCATV mobile terminal may obtain contents delivered from the CATVstations, to which the user has not subscribed.

Further the more, while it has been described in the present embodimentthat the subscriber station is connected with the CATV stations,preferably, through a wide-area LAN, according to the present invention,the subscriber station may be connected with the CATV stations throughany other network such as for example, leased lines or dedicated lines.

INDUSTRIAL APPLICABILITY

The present invention can provide a cable television system, a relayapparatus, a center apparatus, and a cable television service providingmethod, which makes it possible for a user to receive a cable televisionservice from a relay apparatus when the user is located in a servicearea of any one of the relay apparatuses.

1. A cable television system, comprising: a mobile communicationterminal mounted on a movable object and capable of establishing aconnection with a cable television service line by wireless; a pluralityof relay apparatuses respectively installed in a plurality of serviceareas, and each of said relay apparatuses being operative to delivercommon contents concerning a cable television service to said mobilecommunication terminal located within each of said service areas; and acenter apparatus connected with each of said relay apparatuses through acommunication line, for delivering common contents to said relayapparatuses by way of multicast communication, and in which said mobilecommunication terminal located within a service area is operative totransmit a log-in request to said relay apparatus installed in saidservice area by wireless, said relay apparatus is operative to transmituser identification information of said mobile communication terminaland specifying information for specifying said relay apparatus to saidcenter apparatus, said center apparatus is operative to transmitauthentication information to said relay apparatus, which havetransmitted said specifying information, when said user identificationinformation is valid, upon receiving said specifying information, saidrelay apparatus is operative to start a cable television service forsaid mobile communication terminal on the basis of said authenticationinformation, upon receiving said authentication information, said mobilecommunication terminal is operative to transmit request information forcommon contents to said relay apparatus, said relay apparatus isoperative to transmit a request for delivering common contents to saidcenter apparatus, upon receiving said request information for commoncontents from said mobile communication terminal, and said centerapparatus is operative to deliver common contents to said mobilecommunication terminal through said relay apparatus and store thereinand manage delivery history information indicative of a history ofdelivering contents, in response to said request for delivering commoncontents from said relay apparatus.
 2. A cable television system as setforth in claim 1, in which said user identification information isconstituted by personal information stored in an IC (integrated circuit)card or a magnetic card.
 3. A cable television system as set forth inclaim 1 or claim 2, in which said center apparatus is operative toperform an accounting process on the basis of said delivery historyinformation indicative of delivering said common contents.
 4. A relayapparatus installed in a service area and connected with a centerapparatus through a communication line, for delivering common contentsconcerning a cable television service received from said centerapparatus to a mobile communication terminal mounted on a movable objectlocated within said service area, said relay apparatus comprises: firstreceiving means for receiving said log-in request when said mobilecommunication terminal transmits a log-in request by wireless;transmitting means for transmitting user identification information ofsaid mobile communication terminal and specifying information forspecifying said relay apparatus, which has received said log-in requestand said user identification information, to said center apparatus uponreceiving said log-in request; second receiving means for receivingauthentication information from said center apparatus when said useridentification information is valid; service providing means forstarting a cable television service for said mobile communicationterminal on the basis of said authentication information; common contentrequest means for transmitting a request for delivering common contentsto said center apparatus, upon receiving request information for commoncontents from said mobile communication terminal; and delivering meansfor delivering common contents received from said center apparatus tosaid mobile communication terminal.
 5. A relay apparatus as set forth inclaim 4, in which said user identification information is constituted bypersonal information stored in an IC (integrated circuit) card or amagnetic card.
 6. A center apparatus for delivering common contents to aplurality of relay apparatuses respectively installed in a plurality ofservice areas by way of multicast communication so that each of saidrelay apparatuses delivers common contents concerning a cable televisionservice to a mobile communication terminal located within each of saidservice areas, said center apparatus comprising: first receiving meansfor receiving user identification information and specifying informationfor specifying said relay apparatus; specific information storage meansfor storing therein personal information on user; transmitting means forjudging whether or not said user identification information is authenticby comparing said personal information stored in said specificinformation storage means with said user identification information andtransmitting authentic information to said relay apparatus specified bysaid specifying information when it is judged that said useridentification information is authentic; second receiving means forreceiving a request for delivering common contents from said relayapparatus; and delivering means for delivering common contents to saidmobile communication terminal through said relay apparatus uponreceiving said request for delivering common contents from said relayapparatus.
 7. A center apparatus as set forth in claim 6, furthercomprising storage means for storing therein delivery historyinformation indicative of a history of delivering said contents; andaccounting means for performing an accounting process on the basis ofsaid delivery history information stored in said storage means.
 8. Acenter apparatus as set forth in claim 6 or claim 7, in which said useridentification information is constituted by personal information storedin an IC (integrated circuit) card or a magnetic card.
 9. A method ofproviding a cable television service of providing a cable televisionservice to a mobile communication terminal through a relay apparatusfrom a center apparatus, comprising; (a) preparing a mobilecommunication terminal mounted on a movable object and capable ofestablishing a connection with a cable television service line bywireless; a plurality of relay apparatuses respectively installed in aplurality of service areas, and each of said relay apparatuses beingoperative to deliver common contents concerning a cable televisionservice to said mobile communication terminal located within each ofsaid service areas; and a center apparatus connected with each of saidrelay apparatuses through a communication line, for delivering commoncontents to said relay apparatuses by way of multicast communication;(b) transmitting a log-in request to said relay apparatus installed insaid service area by wireless, by said mobile communication terminal;(c) transmitting user identification information of said mobilecommunication terminal and specifying information for specifying saidrelay apparatus to said center apparatus, by said relay apparatus; (d)transmitting authentication information to said relay apparatus, whichhave transmitted said specifying information, when said useridentification information is valid, upon receiving said specifyinginformation, by said center apparatus; (e) starting a cable televisionservice for said mobile communication terminal on the basis of saidauthentication information, by said relay apparatus; (f) transmittingrequest information for common contents to said relay apparatus, by saidmobile communication terminal; (g) transmitting a request for deliveringcommon contents to said center apparatus, upon receiving said requestinformation for common contents from said mobile communication terminal,by said relay apparatus; (h) delivering common contents to said mobilecommunication terminal through said relay apparatus in response to saidrequest for delivering common contents from said relay apparatus, bysaid center apparatus; and (i) storing therein and managing deliveryhistory information indicative of a history of delivering contents. 10.A method of providing a cable television service as set forth in claim9, in which said user identification information is constituted bypersonal information stored in an IC (integrated circuit) card or amagnetic card.
 11. A method of providing a cable television service asset forth in claim 9 or claim 10, in which said step (i) has a step ofperforming an accounting process on the basis of said delivery historyinformation indicative of delivering said common contents.